Hello, we have added additional space to the master bedroom, making room for a larger bath. The small bath we now have will be converted into a walk-in closet. Current plumbing in the small bath is: toilet center, shower right of toilet and vanity to the left. The waste stack is offset under the toilet and the elbow connection for the toilet enters the stack, there is a vent to the roof directly above stack. The shower and vanity enter from stack above the toilet on either side and there is a vent for the vanity that goes above the vanity drain in the wall, then it crosses over and connects to the main roof vent. There is no such vent for the shower. Now, we want to move the bath to the opposite side of the bedroom. this will have about the same configuration as the old bath (vanity-toilet-then shower). Our dilemma, we would like to run the waste, vanity and shower about 24 feet, back to the original waste stack and roof vent. The new drain will have two 90 degree turns and one drop into the original stack. There will be plenty of room for the proper pitch (1/8 to 1/4th inch per foot with 4" pipe). Now I know that we will need air admittance to make for the right pressure for the flow of each station, can we get this needed air from air admittance valves along the length of the new line while maintaining the original roof vent where the new line will enter the old stack? Hope this is clear; not a plummer but have gotten 4 estimates with 4 different opinions!

What do the people who have given estimates say? If I were one of them, I would not care one bit about what YOU think, I would do it my way.

You would PROPOSE your way.

You would bid on the SPECIFICATIONS and do it THAT way.

Unless the 'specs' are not code compliant, then you would make your NEW proposal.


proper procedure for the Original Poster owner/builder:

Obtain several proposals. (with or without prices)

Select the proposal that suits you. (that proposal becomes the 'specs')

Add requirement for license - bonding - insurance - permit and 'signoff'.

THEN get quotes so you are comparing apples to apples.

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

So, you are saying, "tell him HOW you will do it, and then he can use your design to get prices from others, (or do it himself that way)? NO WAY. I see the job and give a price to do it, period.

pipe the shower like this. put the AAV where it shows an open vent.
make sure the AAV is accessible.
whether the drain length is 4 feet to the stack or 24 feet it makes no difference. the location of the AAV is what is important..

hj,

no, not tell him how, but do tell him what, or bid on customer's location sketch or proposal

eg.

provide xyz type of material (Cu/CPVC/PEX/etc) and necessary labor to install the following bath fixtures (list of brand/model/color) in the following location: xyz (provide location sketch)

specify method of venting (loop, wet, individual, AAV)

specify responsibility for 'room finishing'

guarantee (via bond) code compliance and 'sign-off'

provide copy of license and insurance


WHAT, not HOW


the point, from the OP's perspective, is to obtain pricing for IDENTICAL finished work - the actual piping lay-out may differ from plumber to plumber, but the fixtures and material comparison needs to be apples to apples

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

geesh bernabeau... i don't know about you area but in my neck of the woods the only way a customer would be able to get a detailed proposal like that would be to hire an architect.
this would cost them at least 1000 to 1500 dollars.
add to that the cost of the many revisions that inevitably occur and the design phases of the project will cost 30-40% of the 3 fixture installation.
note... all contractors are not crooks..
some of us can be trusted to do a proper job at a reasonable cost.

yes, we can ......

but

from the customer's viewpoint

what if we did NOT ?



I described the perfect way,

the point is: compare apples to apples.



eg.

relocate existing bath fixtures as follows: (simple pencil sketch)

use area consistent piping (type)

pull permit and obtain sign-off

copy of license and insurance

customer/plumber responsible for room finish/patch/paint



else: "But that's what the contractor gave me!" from the customer

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

If he customer did not trust us, why did he call us in the first place? Other than new construction and TI's, I seldom had a formal contract with my customers. We dealt on trust and confidence in each other.

Why can't you run a 2" vent from the new to old locations?

? .............. because it would cost money .................. ?

==============================================

"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638